@article{LehmannJorgensenFratzetal.2021,
  author    = {Lehmann, Julian and J{\o}rgensen, Morten E. and Fratz, Stefanie and M{\"u}ller, Heike M. and Kusch, Jana and Scherzer, S{\"o}nke and Navarro-Retamal, Carlos and Mayer, Dominik and B{\"o}hm, Jennifer and Konrad, Kai R. and Terpitz, Ulrich and Dreyer, Ingo and Mueller, Thomas D. and Sauer, Markus and Hedrich, Rainer and Geiger, Dietmar and Maierhofer, Tobias},
  title     = {Acidosis-induced activation of anion channel SLAH3 in the flooding-related stress response of Arabidopsis},
  series = {Current Biology},
  volume    = {31},
  journal   = {Current Biology},
  doi       = {10.1016/j.cub.2021.06.018},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-363320},
  pages     = {3575-3585},
  year      = {2021},
  abstract  = {Plants, as sessile organisms, gained the ability to sense and respond to biotic and abiotic stressors to survive severe changes in their environments. The change in our climate comes with extreme dry periods but also episodes of flooding. The latter stress condition causes anaerobiosis-triggered cytosolic acidosis and impairs plant function. The molecular mechanism that enables plant cells to sense acidity and convey this signal via membrane depolarization was previously unknown. Here, we show that acidosis-induced anion efflux from Arabidopsis (Arabidopsis thaliana) roots is dependent on the S-type anion channel AtSLAH3. Heterologous expression of SLAH3 in Xenopus oocytes revealed that the anion channel is directly activated by a small, physiological drop in cytosolic pH. Acidosis-triggered activation of SLAH3 is mediated by protonation of histidine 330 and 454. Super-resolution microscopy analysis showed that the increase in cellular proton concentration switches SLAH3 from an electrically silent channel dimer into its active monomeric form. Our results show that, upon acidification, protons directly switch SLAH3 to its open configuration, bypassing kinase-dependent activation. Moreover, under flooding conditions, the stress response of Arabidopsis wild-type (WT) plants was significantly higher compared to SLAH3 loss-of-function mutants. Our genetic evidence of SLAH3 pH sensor function may guide the development of crop varieties with improved stress tolerance.},
  language  = {en}
}